package org.linlinjava.litemall.web.util;

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Map;

import org.apache.commons.lang3.StringUtils;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTCreator;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTCreationException;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.auth0.jwt.interfaces.Claim;
import com.auth0.jwt.interfaces.DecodedJWT;

public class JwtHelper {
	// 秘钥
	static final String SECRET = "I-Lumiere-Token";
	// 签名是有谁生成
	static final String ISSUSER = "LUMIERE";
	// 签名的主题
	static final String SUBJECT = "this is Lumiere token";
	// 签名的观众
	static final String AUDIENCE = "MINIIPAD";
	
	
	public String createToken(Integer userId, String userName){
		try {
		    Algorithm algorithm = Algorithm.HMAC256(SECRET);
		    Map<String, Object> map = new HashMap<String, Object>();
		    Date nowDate = new Date();
		    // 过期时间：8小时
		    Date expireDate = getAfterDate(nowDate,0,1,0,0,0,0);
	        map.put("alg", "HS256");
	        map.put("typ", "JWT");
			JWTCreator.Builder builder = JWT.create();

			String token = builder
		    	// 设置头部信息 Header
		    	.withHeader(map)
		    	// 设置 载荷 Payload
		    	.withClaim("userId", userId)
				.withClaim("userName", userName)
		        .withIssuer(ISSUSER)
		        .withSubject(SUBJECT)
		        .withAudience(AUDIENCE)
		        // 生成签名的时间 
		        .withIssuedAt(nowDate)
		        // 签名过期的时间 
		        .withExpiresAt(expireDate)
		        // 签名 Signature
		        .sign(algorithm);
		    return token;
		} catch (JWTCreationException exception){
			exception.printStackTrace();
		}
		return null;
	}

	public String createToken(Map<String, Integer> claimMap){
		try {
			Algorithm algorithm = Algorithm.HMAC256(SECRET);
			Map<String, Object> map = new HashMap<String, Object>();
			Date nowDate = new Date();
			// 过期时间：一天 24小时
			Date expireDate = getAfterDate(nowDate,0,0,1,0,0,0);
			map.put("alg", "HS256");
			map.put("typ", "JWT");
			JWTCreator.Builder builder = JWT.create()
					// 设置头部信息 Header
					.withHeader(map)
					.withIssuer(ISSUSER)
					.withSubject(SUBJECT)
					.withAudience(AUDIENCE)
					// 生成签名的时间
					.withIssuedAt(nowDate)
					// 签名过期的时间
					.withExpiresAt(expireDate);

			claimMap.forEach((key,value)->{
				builder.withClaim(key, value);
			});
			String token = builder.sign(algorithm);
			return token;
		} catch (JWTCreationException exception){
			exception.printStackTrace();
		}
		return null;
	}

	public Integer verifyTokenAndGetUserId(String token) {
		try {
		    Algorithm algorithm = Algorithm.HMAC256(SECRET);
		    JWTVerifier verifier = JWT.require(algorithm)
		        .withIssuer(ISSUSER)
		        .build();
		    DecodedJWT jwt = verifier.verify(token);
		    Map<String, Claim> claims = jwt.getClaims();
		    Claim claim = claims.get("userId");
		    return claim.asInt();
		} catch (JWTVerificationException exception){
//			exception.printStackTrace();
		}
		
		return null;
	}


	public Integer verifyTokenAndGetShopId(String token) {
		try {
			Algorithm algorithm = Algorithm.HMAC256(SECRET);
			JWTVerifier verifier = JWT.require(algorithm)
					.withIssuer(ISSUSER)
					.build();
			DecodedJWT jwt = verifier.verify(token);
			Map<String, Claim> claims = jwt.getClaims();
			Claim claim = claims.get("shopId");
			return claim.asInt();
		} catch (JWTVerificationException exception){
//			exception.printStackTrace();
		}

		return null;
	}

	public String verifyTokenAndGetUserName(String token) {
		try {
			Algorithm algorithm = Algorithm.HMAC256(SECRET);
			JWTVerifier verifier = JWT.require(algorithm)
					.withIssuer(ISSUSER)
					.build();
			DecodedJWT jwt = verifier.verify(token);
			Map<String, Claim> claims = jwt.getClaims();
			Claim claim = claims.get("userName");
			return claim.asString();
		} catch (JWTVerificationException exception){
//			exception.printStackTrace();
		}

		return "";
	}
	
	public boolean verifyToken(String token) {
		if (StringUtils.isBlank(token)) {
			 return false;
		 }
		
		try {
			Algorithm algorithm = Algorithm.HMAC256(SECRET);
			JWTVerifier verifier = JWT.require(algorithm)
					.withIssuer(ISSUSER)
					.build();
			DecodedJWT jwt = verifier.verify(token);
			Date expTime = jwt.getExpiresAt();
			if (expTime.getTime() > System.currentTimeMillis()) {
				return true;
			}
		} catch (JWTVerificationException exception){
			
		}
		return false;
	}

	public  Date getAfterDate(Date date, int year, int month, int day, int hour, int minute, int second){
		if(date == null){
			date = new Date();
		}
		
		Calendar cal = new GregorianCalendar();
		
		cal.setTime(date);
		if(year != 0){
			cal.add(Calendar.YEAR, year);
		}
		if(month != 0){
			cal.add(Calendar.MONTH, month);
		}
		if(day != 0){
			cal.add(Calendar.DATE, day);
		}
		if(hour != 0){
			cal.add(Calendar.HOUR_OF_DAY, hour);
		}
		if(minute != 0){
			cal.add(Calendar.MINUTE, minute);
		}
		if(second != 0){
			cal.add(Calendar.SECOND, second);
		}
		return cal.getTime();
	}

}
